Sewing machine attachment for circular stitching



Nov. 12, 1968 SUSUMU HANYU 3,410,237

SEWING MACHINE ATTACHMENT FOR CIRCULAR STITCHING Filed June 25, L966 2 sheets-sneak INVENTOR. H 5/ 5 Liana 4a,,

Maw j fnu.

I Nov. 12, 1968 SUSUMU HANYU SEWING MACHINE ATTACHMENT FOR CIRCULAR STITCHING Filed June 23, 1966 2 Sheets-Sheet 2 INVENTOR. 5 44 na Hwy a MM WWW United States Patent W 3,410,237 SEWING MACHINE ATTACHMENT FOR CIRCULAR STITCHING Susumu Hanyu, Tokyo, Japan, assignor to Janome Sewing Machine Co., Ltd., Tokyo, Japan Filed June 23, 1966, Ser. No. 559,942 Claims priority, application Japan, June 29, 1965, 40/52,620, 40/52,621, 40/52,622 13 Claims. (Cl. 112-102) ABSTRACT OF THE DISCLGSURE An attachment for a sewing machine has an annular driven rotary feeding member for rotating a fabric. The needle passes through a central opening of the feeding means and penetrates the fabric at a point spaced from the axis of rotation so that a circular seam is formed in the fabric.

The present invention relates to an attachment for circular stitching which is used with a sewing machine of the type in which the needle oscillates to make zig-zag or other ornamental stitches.

It is the main object of the invention to provide an attachment for a standard zig-zag sewing machine for making stitches along circular lines, particularly for eyelets or for embroidery including circular patterns.

Standard sewing machines are provided with a feeding means for the fabric by which the fabric is transported along a straight path so that the needle produces Zig-zag stitches along a straight line. If the feeding means were modified to cause rotation of the fabric in order to permit the needle to stitch along -a circular line, the structure of the feeding means would be so substantially modified, that it would not be possible to make a straight line of stitches, and a machine which is only suited for a very special purpose would result.

It is another object of the invention to provide an attachment for standard sewing machines which permits the sewing of straight seams when the attachment is not used, and of circular seams when the attachment is used.

It is possible to make a row of stitches along a curved line by manually moving and turning the fabric while the nee-die stitches the fabric. However, the curvature of the stitched pattern cannot be exactly determined, and consequently not repeated.

It is another object of the invention to provide a sewing machine with means permitting the stitching of precise circles whose diameter is known, and which can be exactly repeated.

Another object of the invention is to provide a sewing machine with an attachment for circular stitching which can be operated by unskilled workers.

Another object of the invention is to provide a simple and compact attachment for a sewing machine by which stitches along a circular line can be made on a fabric.

It is known to stretch a fabric on a large frame, and to then stitch the fabric. Since this frame is rather large, the structure for supporting the same, and the effort by the operator to move the frame are considerable.

In the present invention, the fabric is rotated by special feeding means which press the fabric onto the support table of the machine, and the needle is arranged in a position eccentric to the center of rotation of the fabric, so that the needle stitches the fabric along a circular line.

The attachment of the present invention is used with a sewing machine, preferably of the z'ig-zag type, which includes drive means, a needle bar with a needle reciprocated by the drive means, and a presser member to which during the usual sewing operations, a presser foot is at- 3,410,237 Patented Nov. 12, 1968 tached for pressing the fabric against the top face of the support table or bed.

One embodiment of the invention comprises support means; means for detachably securing the support means to the sewing machine; feeding means adapted to engage a fabric on the sewing machine and being mounted on the support means for rotary movement about an axis spaced from the needle; and operating means driven from the drive means of the sewing machine and mounted on the support means operatively connected with the feeding means for moving the latter together with the fabric about the axis provided by the support means so that the needle stitches the rotaing fabric along a circle.

In a preferred embodiment of the invention, the support means includes a bearing part having a circular bearing opening, a support part for supporting the bearing part, and means for detachably attaching the support part to the presser member of the sewing machine in a position in which the center of the bearing opening is spaced from the needle. The feeding means is an annular plate having a bottom face, preferably knurled or serrated, to engage a fabric located on the support table and having a center part mounted in the bearing opening for rotation about a vertical axis spaced from the needle. The center part has an opening through which the needle passes into and out of the fabric in a position spaced from the axis of rotation of the feeding means. Since the support means is attached to the presser member, it is lowered with the annular feeding plate when the pressure member is moved down to an operative position, and the bottom face of the annular feeding plate is frictionally coupled with the fabric. The operating means include a member coupled with the needle bar and reciprocated by the same to rotate the annular feeding plate through a pawl and ratchet connection. In this manner, the reciprocating motion of the needle bar with the needle, causes stepwise turning of the feeding plate with the fabric, and since the needle is spaced from the axis of rotation of the annular feeding plate and of the fabric, stitches are made along a circular line having its center in the axis of rotation of the annular feeding plate and of the fabric.

In the preferred embodiment of the invention, the operating means includes a lever abutting a projecting portion of the needle bar, and carrying a spring loaded pawl cooperating with a ratchet wheel secured to the top face of the annular feeding plate. The position of the support means on the presser member, and thereby the position of the entire attachment can be adjusted, and adjusted positions are indicated by an indicator member secured to the support means.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a front view illustrating a sewing machine provided with the adapter according to the invention;

FIG. 2 is a fragmentary side elevation illustrating an embodiment of the invention;

FIG. 3 is a plan view of the embodiment of FIG. 2;

FIG. 4 is a perspective View illustrating the embodiment of FIGS. 2 and 3;

FIG. 5 is a perspective exploded view of the embodiment of the attachment shown in FIGS. 1 to 4; and

FIG. 5a is a bottom view of an annular feeding member shown in a top view in FIG. 5.

Referring now to the drawings, a conventional Zig-Zig sewing machine has a needle bar 110 to which a needle 112 is attached by a manually operated screw 111. A presser member or rod 160 is provided to which during the usual operation of the sewing machine, a presser foot is attached by a screw 101. When the attachment of the invention is used, the conventional feeding means are placed in an inoperative condition by setting a manually operated knob. The inoperative condition of the standard feeding dog is also required for making bar tack stitches at the ends of button holes, and for other ornamental stitches, so that zig-zag machines of the type with which the present invention is concerned, can be set to a condition in which the fabric is neither forward nor rearward transported.

The attachment of the invention substitutes rotary feeding machines which cause rotation of the fabric on the horizontal support plate of the machine.

The attachment illustrated in the drawing includes a feeding means 1 shown to be an annular or circular plate 16 having a central collar 13 provided with an annular recess 14. As best seen in FIG. 5a, the bottom face of the annular plate 16 has a central annular portion 12 which is knurled or serrated, and when this bottom face is placed on a fabric lying on the top surface of the machine bed or table 200, serrations 12 couple feeding means 1 with the fabric so that the fabric rotates when feeding means 1 is rotated.

In assembled condition, the collar 13 is inserted into a central bearing opening 22a of a bearing part 22 which together with a support plate 27 constitutes a bearing 16, so that a resilient ring can be snapped into groove 14 for securing feeding plate 16 against axial movement, while permitting rotation of feeding plate 1 about an axis passing through the center of the bearing opening 22a. Support plate 27 has two bores 23 and 24 and is mounted on a support 3 for limited pivotal movement. For this purpose, a pivot screw 7 passes through a bore 35 in a support plate 31 of support means 3 and through bore 23 in support plate 27 and turnably supports bearing means 2 to permit angular adjustment of bearing means 2. Support plate 31 has an elongated slot 36 which registers with bore 24 in support plate 27. An arresting screw 8 is inserted through slot 36 and bore 24 and carries a nut on a threaded portion 81 which permits the clamping together of support plates 27 and 31 in angularly adjusted positions turned about pivot 7.

Support means 3 has an upright angular wall 32 terminating at one end in an attaching portion 34 which fits onto the flattened end of presser rod 100. As best seen in FIGS. 2 and 3, attaching portion 34 is placed on presser rod 100 and secured to the same by a screw 101 which has a large head for convenient manual manipulation. Since supporting means 3 is thus supported by presser rod 100, bearing means 2 and feeding means 1 are also supported on the same, and the design and construction of support means 31 is selected so that the needle 112 is located within the center opening surrounded by collar 13 of feeding means 1, but radially spaced from, and eccentric to, the axis of rotation of feeding means 1 which is determined by the center of the bearing opening 22a. As clearly shown in FIG. 3, the axis of rotation of feeding means 1 is located in the center of opening 15, and the needle is located at the center of the needle bar 110.

Support plate 31 has two small bores 37 receiving a pair of screws 62, 62 passing through openings 63, 63' in an indicator arm 64 which has an index mark 61. Bearing part 22 has corresponding indicia including plus and minus signs so that when arresting screw 8 is loosened, and bearing means 2 is angularly adjusted relative to support means 3 and presser rod 100, the position is indicated by index mark 61. By such adjustment,

the distance of needle 112 from the axis of rotation of feeding means 1 can be adjusted, changed, and again set to a previously indicated position. An operating lever 4 has a U-shaped end portion in which a pair of aligned bores 42 is provided. A pivot pin 9 passes through bores 42 and is secured by a threaded portion 91 in bore 33 of wall 32. An annular recess 92 projects out of wall 44 and is engaged by a spring washer 93. A coil spring 94 surrounds pin 9 and has end portions 95 and 96 respectively engaging wall 32 and the inside of portion 41 so that lever 4 is biased to turn from the position illustrated in FIG. 2 in solid lines to the position shown in broken lines. Since lever 4 abuts screw 111 on needle bar 110, it assumes its higher position when the needle bar moves upward with needle 112, and moves downward during the down stroke of the reciprocating needle 112.

U-shaped member 41 has another pair of aligned bores 43 through which a pin 56 passes. Pin 56 also passes through the aligned bores 53 in a pair of ears 55 of a pawl 5, so that pawl 5 is supported for angular movement. One free end of pivot pin 56 projects into the rectangular opening 38 in the upright wall 32 of support means 3 to limit the angular movement of lever 4 so that the same does not move below the position illustrated in broken lines in FIG. 2 while the needle continues its downward movement.

Pawl 5 has an engaging portion 51 cooperating with an annular ratchet 11 provided at the top of annular feeding member 16. The other end of pawl 5 has a boss 52 with a recess 52 for holding the end of a small coil spring 54 whose other end abuts the top of support plate 31.

The position of pawl 3 in relation to support plate 31 and ratchet 11, is best seen in FIG. 3 which also shows lever 4 resting on the projecting screws 111 under the action of spring 94.

The attachment is used in the following manner:

The standard presser foot, not shown, is removed from the presser rod 100, and the machine is set to a condition in which the standard feed dog does not transport a fabric lying on the top face of support table 200. The assembled attachment, as shown in FIG. 4, is attached to the flattened end of presser rod 100 by placing the angular attaching portion 34 on the end of the presser rod 100, and securing screw 101.

Assuming that the presser rod 100 is in its upper inoperative position, the serrations 12 on the bottom face of feeding means 1 are slightly spaced from the top surface of the support table of the sewing machine, and a fabric can be inserted between the bottom face of am nular feeding member 16 and the top surface of the support table 200. When a portion of the fabric appearing in the opening 15 is in a desired position, the presser rod 100 is lowered to its operative position in which a spring, not shown, urges presser rod 100 with the attachment downward so that the serrations 12 engage the top surface of the fabric.

When the machine is started, drive means of the sewing machine reciprocate needle bar 10 with projecting screw 111 and needle 112 so that the needle moves downward passing through the central opening 15 into the fabric. During the downward stroke of the needle bar, lever 4 is urged by spring 94 to follow such movement to the position indicated in broken lines FIG. 2 in which lever 4 is stopped by engagement between the projecting end of pin 56 with an edge of opening 38 of wall 32.

During this downward stroke of lever 4, pawl 5 is retracted and moves over the backs of the ratchet teeth of the annular ratchet 11. The needle continues its downward movement and penetrates fabric 15. During the following upward stroke of the needle, screw 111 again engages lever 4 in a position in which the needle 112 is already located above the fabric. During the movement of lever 4 from the position shown in broken lines to the position shown in solid lines, ratchet pawl 5 is moved forward and since spring 54 urges pawl 5 into a position in which engaging portion 51 is coupled with the ratchet teeth of ratchet 11, the ratchet and the annular feeding plate 1 are turned in clockwise direction as viewed in FIG. 3 about a vertical axis defined by the center of collar 13 and bearing bore 22a. Since needle 11 is positioned spaced from this axis, the following stitches made by the needle are located along a circular line whose center is located in the axis of rotation of the annular feeding member 16. During the next downstroke of the needle, pawl 5 will again be retracted by lever 4, and during the following up stroke, the annular feeding member 16 will be again turned in clockwise direction. In this manner, a circular row of stitches is made in the fabric.

The radius of the line of stitches can be adjusted by loosening arresting screw 8 and by turning bearing means 2 about pivot 7. Adjusted positions are indicated by the index mark 61 pointing to different indicia 25 on annular bearing part 22.

As best seen in FIG. 5a, the serrated annular portion 12, and the annular ratchet portion 11 of feeding member 16 are spaced from the outer periphery of feeding member 16 by a flange portion 16a. The rotating fabric is held in place by flange portion 16a, and is prevented from forming folds, and from being snagged between pawl 5 and ratchet 11.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of attachments for sewing machines dilfering from the types described above.

While the invention has been illustrated and described as embodied in an attachment for rotating a fabric on the table of a sewing machine so that stitches are formed along a circular line, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended vw'thin the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a sewing machine including drive means, a needle bar operated by said drive means, and a needle on said needle bar, in combination, an attachment for circular stitching comprising support means including an annular bearing ring having a bearing opening; attaching means for detachably securing said support means to said sewing machine; feeding means adapted to engage a fabric on said sewing machine, and including a feeding plate including a central collar having a central opening, said collar being mounted in said bearing bore for rotation about an axis, said feeding plate having a bottom surface adapted to engage the fabric; said support means supporting said feeding plate in a position in which said needle passes through said central opening into the fabric at a point spaced from said axis of rotation; and operating means driven from said drive means and mounted on said support means operatively connected with said feeding means for moving the latter together with said fabric about said axis so that said needle stitches the rotating fabric along a circle.

2. An attachment according to claim 1 wherein said sewing machine includes a support table for a fabric, and a spring-loaded presser member biassed to move toward said support table; and wherein said attaching means clamp said presser member for supporting said support means and said feeding means on said presser member so that said feeding means are resiliently urged by said presser member to engage said fabric on said support table.

3. An attachment according to claim 1 wherein said sewing machine includes a support table for a fabric, and a spring-loaded presser member biassed to move toward said support table; and wherein said attaching means clamp said presser member for supporting said support means and said feeding means on said presser member so that said feeding means are resiliently urged by said presser member to engage said fabric on said support table; and wherein said operating means include a reciprocable operating member connected with said needle bar for reciprocating movement, a pawl reciprocated by said operating member, and a circular ratchet secured to said feeding means for rotary movement about said axis, and being engaged and driven by said pawl during reciprocation of said operating member.

4. An attachment according to claim 1 wherein said sewing machine includes a spring-loaded presser member; wherein said support means includes a first support plate, and an upright wall secured to said first support plate and having a projecting portion for engaging said presser member, said support means further including a bearing member having a second support plate mounted for pivotal movement on said first support plate and a bearing portion for rotatably supporting said feeding means; and wherein said operating means include an operating member mounted on said upright wall of said support means for angular reciprocating movement and being connected with said needle bar so as to be reciprocated by the same, said operating means further including a pawl reciprocated by said operating member, and a circular ratchet secured to said feeding means and rotated by said pawl for rotating said feeding means.

5. An attachment according to claim 4 wherein said operating means include a pivot pin for mounting said pawl on said operating member; and wherein said upright wall has an opening into which said pivot pin projects for limiting movement of said operating member so that said pawl does not turn said feeding means while said needle penetrates into the fabric.

6. An attachment as claimed in claim 1 wherein said operating means include an annular ratchet on the top face of said feeding plate spaced inwardly from the periphery thereof, and a reciprocating pawl operatively connected with said needle bar and operated by the same to stepwise engage said annular ratchet so that an unnular peripheral portion of said feeding plate between said annular ratchet and the periphery of said feeding plate prevents the fabric from being snagged between said ratchet and said pawl.

7. An attachment as claimed in claim 1 wherein said support means include a first support member secured to said sewing machine, and a second support member including said bearing means, and being mounted on said first support member for angular adjustment together with said bearing means and relative to said needle, and means for securing said first and second support members in adjusted positions to each other whereby the distance between said needle and said axis of rotation can be varied.

8. An attachment as claimed in claim 7 wherein said support means include an indicator arm having an indicating portion located above said central opening; and wherein said bearing means include a fiat ring surrounding said collar and having indicia for indicating the angular adjustment of said bearing means.

9. An attachment as claimed in claim 1 wherein said operating means include a flat annular ratchet surface on the top face of said feeding plate, an operating lever oscillated by said needle bar, and a ratchet pawl mounted on said lever for movement about an axis parallel to said feeding plate, and a spring urging said pawl into engagement with said ratchet.

10. In a sewing machine including a support table,.

prcsser member movable toward said table from an inoperative position to an operative position, in combination, an attachment for circular stitching comprising, support means including an angularly adjustable bearing part having a circular bearing opening, a support for supporting said bearing part, and attaching means for detachably attaching said support to said presser member in a position in which the center of said bearing opening is spaced from said needle; feeding means having a bottom face confronting said support table and adapted to engage a fabric located on said support table under said feeding means, said feeding means including a central collar mounted in said bearing opening for rotation about a vertical axis spaced from said needle and having an opening through which said needle passes into and out of the fabric spaced from said axis, said bottom face being pressed against the fabric in said operative position of said presser member; and operating means mounted on said support part coupled with said needle bar annd driven by the same, said operating means being operatively connected with said feeding means for rotating the same together with said fabric about said axis so that said needle stitches the rotating fabric along a circle.

11. An attachment according to claim 10 and including an indicator arm secured to said support and having an indicating portion located in the region of said opening in said central collar of said feeding means, and indicia on said bearing part adjacent said circular bearing opening and said central part; and means mounting said bearing part on said support for angular adjustment so that angularly adjusted positions of said bearing part and of said feeding means are indicated by said indicator arm and by said indicia.

12. An attachment according to claim 10 wherein said feeding means includes an annular plate having said central part, an annular ratchet on the top face thereof, and annular serrations on the bottom face thereof, said annular plate having a smooth peripheral flange for preventing snagging of the fabric in said ratchet; and wherein said operating means include a reciprocating pawl cooperating with said ratchet.

13. An attachment according to claim 10 wherein said operating means includes an operating lever, spring means urging said operating lever into coupling engagement with said needle bar; and including stop means limiting the angular displacement of said operating lever so that said operating lever follows the downward stroke of said needle bar and needle only partly, said operating means further including a pawloperated by said lever and annularly ratchet on said feeding means cooperating with said pawl so that feeding means is stepwise rotated during angular reciprocation of said operating lever.

References Cited UNITED STATES PATENTS 1,431,591 10/1922 Lucy 112IO2 3,059,599 10/1962 Taketomi 112102 JORDAN FRANKLIN, Primary Examiner. 

